A microkeratome for keratomileusis ophthalmic surgery having a base, a carriage mounted to the base and a cutting blade carried in the carriage. The carriage is guided for movement in an axial cutting direction and the cutting blade is movable in an oscillating motion transverse to the cutting direction. In addition, the carriage is movable in the cutting direction without imparting the oscillating motion to the cutting blade.
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12. A microkeratome connectable to a controller through at least one control cable having a shaft movable within a sheath, comprising: a base mountable on a patient's eye; a carriage mounted to the base and movable along a linear path relative to the base; a cutting blade supported by the carriage for oscillating movement relative to the carriage transverse to the path; wherein the carriage has a curved surface from which the cutting blade extends, the carriage is connectable to the shaft and the base includes an anchor that is connectable to the sheath such that movement of the shaft relative to the sheath effects at least movement of the carriage relative to the base.
1. A system for keratomileusis ophthalmic surgery comprising:
a microkeratome for cutting a section of a cornea of an eye including a base having an anchor, a carriage mounted to the base and a cutting blade carried in the carriage, the carriage having a curved surface from which the cutting blade extends, the carriage being movable with respect to the base, and the cutting blade being movable relative to the carriage; and a control assembly for controlling the microkeratome, the control assembly including a cable having a sheath, a shaft movable within the sheath, and a controller that controls the movement of the shaft, the shaft being connected to the carriage, and the sheath being connected to the anchor to fix the sheath relative to the base such that axial movement of the shaft effects linear movement of the carriage relative to the base. 7. A method for keratomileusis ophthalmic surgery comprising:
providing a microkeratome including a base having an anchor, a carriage mounted to the base and a cutting blade carried in the carriage, the carriage having a curved surface from which the cutting blade extends, the carriage being movable with respect to the base and the cutting blade being movable with respect to the carriage; providing a control assembly for controlling the microkeratome, the control assembly including a cable having a sheath, a shaft movable within the sheath, and a controller that controls the movement of the shaft, the shaft being connected to the carriage, and the sheath being connected to the anchor to fix the sheath relative to the base such that axial movement of the shaft effects linear movement of the carriage relative to the base; connecting a drive to the microkeratome to advance and retract the cutting blade; and linearly advancing the cutting blade of the microkeratome from an initial position; wherein connecting the drive to the microkeratome includes connecting the cable to the microkeratome; and connecting the cable to the microkeratome includes connecting the shaft to the carriage and connecting the sheath to the anchor.
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17. A system for ophthalmic surgery, comprising: the microkeratome of
18. A microkeratome as set forth in
19. In combination, a control cable having a shaft movable within a sheath and the microkeratome of
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This application is a continuation of application Ser. No. 09/197,021, filed Nov. 20, 1998 now Pat. No. 6,228,099; which claims the benefit of Provisional Application No. 60/066,725, filed Nov. 21, 1997.
The invention relates to an ophthalmic surgical system and method including a disposable surgical microkeratome and, more particularly, to a surgical system and method for using such a device in laser in situ keratomileusis (LASIK).
In the past thirty-five years, several opthalmic surgical methods and devices have been developed and increasingly are used to change the shape of the cornea to correct vision defects, including myopia, hyperopia and astigmatism.
An early technique included a "primary keratectomy" in which an anterior corneal lenticle is removed by manually pushing a blade of a microkeratome across the cornea. Then a "refractive keratectomy" is performed, wherein an optic correction is carved in the surface of the lenticle with a lathe similar to a contact lens lathe. The lenticle is sutured back in place on the eye. When an even and smooth cut is achieved, the best and most predictable results are obtained. However, the manual microkeratomes are difficult to use and require some skill to propel the blade across the cornea in an even and smooth manner, thereby providing varying qualities of primary keratectomies based on the skill and experience of the surgeon. As a result, the predictability of the refractive correction was minimal.
The methods and devices have evolved over the years to an automated, mechanical movement of the microkeratome blade across the cornea which provides a steady, even cut and which improves the predictability of the refractive correction. Furthermore, the lenticle is not completely severed from the cornea. Instead a flap is cut from the cornea, the back of the flap or the exposed stromal bed is sculpted in situ with a laser to provide the refractive correction, and the flap is replaced without sutures. This procedure is called laser in situ keratomileusis (LASIK). LASIK greatly improves the predictability of the amount of change in refractive correction and greatly reduces the amount of time required for the cornea to heal. In addition, the patient experiences a relative lack of discomfort from this procedure.
Unfortunately, problems still remain with some microkeratomes used to make the flap. Some existing microkeratomes still require the surgeon to estimate the length of the cut to make the flap because the cutting distance is not automated. Furthermore, generally microkeratomes are made of surgical steel which prevents the surgeon from viewing the cornea as the cutting blade oscillates and advances.
Another problem with some microkeratomes is that they are made of many small metal components which are expensive to produce and assemble. The assembled microkeratome may be less than two inches long, and individual components may be much smaller. As a result, cleaning and sterilization of the microkeratome between patients is very difficult. Sometimes the microkeratome must be at least partially disassembled and each component cleaned by hand. Therefore, the existing microkeratomes are difficult or even impossible to maintain in an acceptably sterile condition. Additionally, as one might imagine the assembly of many small parts while wearing sterile gloves is very difficult.
Some existing microkeratomes have one or more of the following problems in addition to those described above. For example, on some microkeratomes the depth of cut is determined by an adjustment plate which must be selected and added to the parts assembled before the operation. A last minute change may require the microkeratome to be disassembled, the adjustment plate changed, and then reassembled. Another problem is that some microkeratomes use a mechanical stop to halt the advance of the cutting blade, thereby stalling the motor. This damages the motor and reduces its useful life. Furthermore, some microkeratomes are relatively heavy, thus placing undue pressure on the eye and hindering precise location on the eye. Yet another problem with some microkeratomes is that a base must be attached to the eye and then a cutting device must be assembled and/or mounted thereon.
Therefore, a microkeratome which is easy to use, disposable or easy to clean, and performs a keratectomy in a consistent, smooth and reliable manner would be desirable.
The present invention provides a microkeratome and an associated opthalmic surgical system and method that overcome problems associated with the use of prior art microkeratomes. The present invention, inter alia, provides for independent control of the axial movement and transverse oscillation of a cutting blade of a microkeratome to provide a consistently high quality lamellar flap in the cornea of an eye. A preferred opthalmic surgical system includes a control assembly that powers and controls the movement of the cutting blade, which control assembly is preferably located remote from the microkeratome. This allows the microkeratome to be pre-assemblable, sterilizable, and preferably disposable. Furthermore, the microkeratome of the present invention preferably is made of a clear plastic, making the microkeratome lightweight and easy to produce and use, while allowing the surgeon to observe the cornea as the blade advances.
More particularly, one aspect of the invention provides a microkeratome for keratomileusis ophthalmic surgery having a base, a carriage mounted to the base and a cutting blade carried in the carriage. The carriage is guided for movement in an axial cutting direction and the cutting blade is movable in an oscillating motion transverse to the cutting direction. In addition, the carriage is movable in the cutting direction without imparting the oscillating motion to the cutting blade.
According to one embodiment of the invention, the movement of the carriage in the axial direction can be automated.
According to another embodiment of the invention, the carriage is connectable to an axial cable having a shaft movable within a sheath. In this embodiment the base of the microkeratome provides an axial retaining clip which engages an axial cable fitting on the cable to hold the sheath such that movement of the shaft imparts movement to the carriage relative to the base.
According to yet another embodiment of the invention, substantially all of the microkeratome is molded from a substantially transparent material.
Another aspect of the invention provides a system for keratomileusis ophthalmic surgery that provides a microkeratome for cutting a section of a cornea of an eye and a control assembly for controlling the microkeratome. The microkeratome provides a base, a carriage mounted to the base and a cutting blade carried in the carriage. The carriage is guided for movement in an axial direction. The control assembly includes an axial drive for generating linear movement and a rotary drive for generating rotational movement independently of the axial drive. The axial drive is connected to the microkeratome to impart axial movement to the carriage in an axial direction relative to the base and the rotary drive is connected to the microkeratome to impart an oscillating movement to the cutting blade transverse to the axial direction. The control assembly also includes a controller which controls the axial drive and the rotary drive.
According to one embodiment of the invention, the axial shaft is connected to the carriage with a coupling that permits the axial cable to rotate without imparting torque to the carriage.
According to another embodiment of the invention, the control assembly includes a suction device for supplying suction pressure to the microkeratome.
The suction device is connected to the microkeratome for generating a partial vacuum in a suction chamber mounted to the base to maintain a position of the base relative to an eye.
According to another embodiment of the invention, the controller stops operation of the axial drive and the rotary drive if the suction pressure drops below a predetermined value.
Yet another aspect of the invention provides a method for keratomileusis opthalmic surgery that includes linearly advancing a cutting blade of a microkeratome from an initial position in an axial direction while simultaneously oscillating the cutting blade in a direction transverse to the axial direction; stopping the linear advance and transverse oscillation of the cutting blade at an end position which is removed from the initial position; and linearly retracting the cutting blade to the initial position without imparting transverse oscillation to the blade.
According to one embodiment of the invention, stopping the linear advance and transverse oscillation of the cutting blade occurs automatically at a predetermined distance from the initial position.
According to another embodiment of the invention, the method includes selecting one of a plurality of microkeratomes which provide for respective depths of cut.
According to another embodiment of the invention, the method includes disposing of a first microkeratome following a first operation and selecting a second microkeratome for a subsequent operation.
According to yet another embodiment of the invention, the method includes automatically stopping the cutting blade when the suction device fails to maintain a predetermined level of suction pressure.
Another aspect of the invention provides a method for keratomileusis opthalmic surgery that includes connecting a disposable microkeratome to a control unit operative to drive and control a cutting action of the microkeratome; using the microkeratome to at least partially remove a section of a patient's cornea; and discarding the microkeratome after use with a single patient.
Yet another aspect of the invention provides a microkeratome having a base, a carriage mounted to the base for movement, and a cutting blade carried by the carriage for movement therewith, and the base and carriage are formed of a molded transparent plastic material.
The foregoing and other features of the invention are hereinafter fully described and particularly pointed out in the claims, the following description and annexed drawings setting forth in detail a certain illustrative embodiment of the invention, this embodiment being indicative, however, of but one of the various ways in which the principles of the invention may be employed.
The present invention provides a system and method using a disposable microkeratome that facilitates the performance of corrective refractive opthalmic surgery, particularly keratomileusis, and more particularly laser in situ keratomileusis, LASIK, with independent control of a transverse oscillating motion, an advancing motion, and a retracting motion of a cutting blade.
Referring now to the drawings in detail and initially to
In contrast, the microkeratome 12, which comes into direct contact with the patient, may be used on a single eye or a pair of eyes on a single patient and then discarded. The microkeratome 12 preferably is formed primarily of a few molded plastic parts that are easy to assemble, whereby the microkeratome is inexpensive to produce. The microkeratome can be provided completely assembled, sterilized and ready for use. Since only the microkeratome 12 comes into contact with the eye, does not require extensive assembly just prior to surgery and is disposable, the system 10 is more easily and more effectively maintained in a clean and sterile condition.
The control assembly 14 is contained within a housing 22 and includes a drive assembly 24, a suction pump 26, and a controller 28. The controller 28 preferably includes an electronic circuit for controlling the operation of the drive assembly 24 and the pump 26. The control assembly 14 also has several input devices connected to the controller, including an ON/OFF switch 30, a one-position suction pedal or switch 31, a two-position foot pedal or switch 32, and a flap length adjustment selector 34, also called a flap hinge positioning system. The input devices permit the surgeon to control several variables in the operation of the system 10, as further described below.
Because each eye is a different size and has a different curvature, the position of a flap hinge or the length of a flap (or the width of a severed section) is desirably selected by the flap length adjustment selector 34 prior to operation of the system 10. As shown in
The microswitch 44 provides a signal to the controller 28 (
Generally, the control assembly 14 (
Returning to
The slide member 52 is mounted on a pair of parallel rods 62 which act as slide guides for directing or guiding the motion of the slide member 52 in a linear direction. A rotary drive motor 60 is carried on the slide member 52 for movement therewith. The axial cable 20 includes an axial drive shaft 64 that is connected to the slide member 52 for translating the linear motion of the slide member 52 to the microkeratome 12 and the rotary cable 18 includes a rotary drive shaft 66 that is connected to the rotary motor 60 for transferring rotational motion to the microkeratome 12. Because the rotary drive motor 60 is mounted on the slide member 52, the rotary drive shaft 66 also simultaneously moves in a linear direction with the slide member 52. Therefore, both the axial drive shaft 64 and the rotary drive shaft 66 linearly advance and retract with the slide member 52.
The rotary drive shaft 66 preferably has a monocoil, double wound or triple wound construction over a central wire or mandrel with the winds pitched in opposite directions to provide torsional rigidity. The rotary drive shaft is preferably made of stainless steel wire due to the strength and endurance limit of stainless steel and, more preferably, the shaft is made of 302 stainless steel. The triple wound construction provides better bidirectional properties as-well as greater flexibility which increase the endurance life of the shaft, compared to a monocoil or double wound construction. The torsional stiffness of the triple wound construction is equivalent to or greater than the double wound construction but its flexural stiffness is less than half that of the double wound construction. This is particularly desirable since the shaft may rotate in a relatively sharp bend, at high speed. Furthermore, the rotary drive shaft 66 is coated with a very thin wall shrink tubing in order to provide a smooth surface to minimize or eliminate vibration. Thus, the rotary drive shaft is designed to rotate at speeds up to twenty thousand revolutions per minute and to provide the necessary torque to the microkeratome 12.
In contrast, the axial drive shaft 64 is preferably double wound over a central wire or mandrel. The winds are pitched in opposite directions to provide some torsional rigidity. The pitch angles, or helix angles, are preferably less than forty degrees to make the shaft more flexible than a traditional push-pull cable. However, the central mandrel or wire is larger in diameter than the wires in the outer layers to increase axial and flexural rigidity. This combination provides optimum flexibility without sacrificing "pushability" or the ability to transmit an axial force from the axial motor 50 to the microkeratome 12.
Both the axial and rotary drive shafts 64 and 66 are disposed in flexible sheathes 68 and 70 respectively. The rotary and axial drive shafts 66 and 64 and sheathes form the rotary drive cable 18 and the axial drive cable 20, respectively. The rotary drive cable 18 and the axial drive cable 20 connect the rotary drive motor 60 and the axial drive motor 50, respectively, to the microkeratome 12. The axial drive shaft 64 moves through the cable 20, as the slide member 52 moves through its range of motion while the rotary drive shaft rotates and moves axially within the sheath 70. Preferably, the inside of the sheathes are coated with a material, such as polytetrafluoroethylene (PTFE), to reduce friction between the sheathes and the cables.
The base 72 includes a suction or support platform 76 and a substantially C-shape anchor or retaining clip 78. The platform 76, shown in
At a front end of the platform 76 between the platform guides 82, a circular opening 84 is provided for receiving a cornea therethough. The circular opening 84 provides a sufficiently large aperture size for cutting a desired size flap in hyperopia. The opening 84 communicates through the top surface 80 (or actually top wall) of the platform 76 to a substantially cylindrical suction chamber 86 provided at the underside of the platform.
The suction chamber 86 is formed in part by a cylindrical suction ring 88 which depends from the top wall 89 of the platform 76 and is larger than the circular opening 84 in the platform 76. The suction ring 88 has a lower circular sealing edge for engaging and sealing against the surface of an eye. The circular opening 84 also is bounded by a sealing edge 91 for sealing against the eye. The sealing edges preferably are beveled to provide an airtight enclosed space or are otherwise configured to form a tight seal with the eye. In addition, the suction chamber 86 may include at its bottom surface thereof a material (coating or sealant) which improves the contact with the eye so that a partial vacuum can be drawn in the suction chamber to hold the platform to the eye. A silicone sealant may be used, for example.
The platform 76 has extending upwardly from a forward end thereof a fixture (or fitting) 90 which preferably performs multiple functions. The fitting provides for attachment of the suction line 16 (
Suction is applied to the suction chamber 86 to create a partial vacuum which retains the platform 76 in a stable and fixed position relative to the eye. Preferably, the suction pump 26 (
The fixture 90 also functions as a handle for manipulating the microkeratome. The surgeon can use the handle to facilitate positioning of the microkeratome on an eye and hold the microkeratome in place until a partial vacuum is drawn in the suction chamber. In fact, the surgeon can alternately use the handle to hold the microkeratome in place during the surgical procedure without using the vacuum hold-down, although this is less desirable.
As mentioned above, the platform 76 has at a back end thereof a retaining clip 78. The retaining clip 78 may be formed integrally with the platform or may be fixed thereto by suitable means, such as one or more anchor drivers inserted, as by snapping, into one or more slots or holes in the platform. Any suitable method of attachment may be used, such as the illustrated T-shape rails 152 or arrow shape clips which snap into position when pressed into corresponding openings in the platform.
Referring briefly to
Returning to the cutting assembly 74, as illustrated in
Behind the sled 110 the cutting head 94 also includes an angled blade guide surface 104 on the underside of the cutting head 94. The blade guide surface 104 is angled relative to the top surface 80 of the platform 76 to-provide a desired cutting angle for the cutting blade.
The cutting head 94 has formed therein a transverse slot 114 that opens to the angled blade guide surface. The slot 114 slidably receives and guides the blade holder 96 (
The cutting blade 98, shown in
As last seen in
As seen in
The blade holder 96 also includes a vertical slot 138 which is perpendicular to the width of the blade holder and perpendicular to the angled blade surface 104. When the blade holder is assembled in the cutting head 94, the slot 138 is aligned with an angled opening or passage 140 in the cutting head 94. The passage 140 also is perpendicular to the transverse slot 114 and parallel to the blade guide surface 104.
The wedge 100 also has a transverse recess 126 in the angled surface 106 which receives a distended portion of the protrusion 120 (
The wedge 100 also includes a pair of protrusions 128 extending substantially perpendicular from the angled top surface 106. These protrusions 128 are adapted to be press fit or otherwise secured in a pair of corresponding recesses 130 (
The thicker side, or the back end of the wedge 100, has a groove 132 extending approximately halfway across the width of the wedge 100 and a bore 134 extending from the deepest portion of the groove 132 and coaxial therewith through the remaining width of the wedge 100. The groove 132 and bore 134 are adapted to receive a T shape pin 135 (
Referring to
Turning to
A fitting 146 on the axial drive cable 20 engages the retaining clip 78 to anchor the cable sheath 68 to the section platform 76 so that movement of the axial drive shaft 64 relative to the platform directly and precisely corresponds to movement of the sliding member 52 (FIG. 1). It is noted that the end of the sheath 68 is anchored to the housing 22. The axial drive shaft 20 (
In contrast, the rotary shaft 66 has a fitting 145 with the eccentric 147 coupled to the rotary shaft 66 (FIG. 1). The eccentric passes through the passage 140 in the cutting head 94 to engage the vertical slot 138 in the blade holder 96. The eccentric is held engaged with the cutting head 94 by a bayonet coupling 149 which engages a pair of opposing pins 151 on a tubular coupling on the cutting head 94. The bayonet coupling is held in place with friction and permits the rotary shaft 66 to rotate in either direction while retaining the fitting and the eccentric in a fixed axial location relative to the cutting head 94.
The system 10 also includes a hand tool 150 (shown in FIG. 1). The hand tool 150 holds the axial and rotary cables 20 and 18, respectively, adjacent the microkeratome 12 to facilitate holding and supporting the cables during an operation. Preferably the hand tool 150 holds the rotary drive cable 20 at an angle such that the end position of the rotary cable 20 will be substantially coaxial with the passage 140 in the cutting head 76 (see FIG. 7).
In operation, the rotary drive motor 60 produces a rotational motion in the rotary drive shaft 66 and the rotary drive shaft transmits the rotary motion to the fitting 145 and the eccentric 147. The eccentric and the vertical slot 138 in the blade holder 96 cooperate to transform the rotary motion of the eccentric to a transverse oscillating motion in the blade holder 96 and the cutting blade 98. The rotary drive shaft 66 preferably rotates at about twelve thousand five hundred revolutions per minute. Preferably the oscillating motion is perpendicular to the direction of motion of the cutting head 94 on the platform 76; however, the slots 114 and 138 in the cutting head and wedge; respectively, and/or the angle of the cutting edge 102 may be varied relative to the direction of motion of the cutting head to optimize the performance of the cutting blade 98.
The rotation created by the rotary drive motor 60 (
As shown in
In summary, the disposable microkeratome 12 includes a cutting assembly 74 and platform assembly 72 combination. The platform assembly 72 is seated on the cornea of an eye and is fixedly located or held thereon. The microkeratome 12 is operated by a remotely located control assembly 14 that directs the movement of the cutting assembly 74 across the platform assembly 72 through two flexible cables 18 and 20.
As will be described in greater detail below with respect to a preferred embodiment, the controller 28 in the control assembly 14 controls the axial motor 50, the rotary motor 60, and the suction pump 26. Based on the description herein, it will be readily apparent to one skilled in the art to weigh the advantages and disadvantages of different control mechanisms and to select one suitable to carry out the present invention. The control assembly 14 can include any of numerous technologies available today or in the future, including but not limited to logic gate controllers, switches and relays, and software programming. Accordingly, one skilled in the art would appreciate that the scope of the present invention is intended to include all such suitable control mechanisms.
The operation of the ophthalmic surgical system 10 according to the present invention will be described below with reference to FIGS. 1 and 11-13. A sterile microkeratome 12 is connected to the control assembly 14 through the suction line 16 and the rotary and axial control cables 18 and 20, respectively, as described above.
As shown in
Before the operation is started, however, the surgeon should select the desired flap length with the flap length adjustment selector 34 described above. The flap length adjustment selector 34 determines how far or how long to drive the axial motor 50 and thus drive the cutting assembly 74 across the opening 84 in the platform 76 to cut the cornea.
Once the surgeon is ready to begin, the two position foot pedal 32 is moved to a forward position and is held there, tripping switch 212. Preferably, the foot pedal 32 is biased to a neutral position between a reverse position and the forward position. When switch 212 is moved from its neutral position to its cut cycle initiate switch, the axial drive motor 50 is energized in a backward direction to retreat the slide member 52 and thus the cutting assembly carriage. The rotary drive motor 60 is not energized during this step and thus the cutting blade 98 (
Tripping the initial position microswitch 68 automatically stops the axial motor 50 and causes a second relay 214 to energize, the first relay 204 to de-energize, and to open switches 205 and 206. The first relay is linked to a direction switch 216 which moves from a reverse position to a forward position when the first relay is energized. The axial drive motor automatically begins to run in a forward axial direction. Simultaneously, the rotary motor 60 is energized to cause the cutting blade 98 (
While continuing to hold the foot pedal 32 in its forward position, the slide member 52 advances, thereby advancing the cutting assembly carriage and transversely oscillating the cutting blade 98 until the hinge position microswitch 70 is tripped by the slide member 52 (or the controller 28 otherwise determines that the cut in the cornea that forms the flap is complete). Tripping the hinge position microswitch 70 stops both motors 50 and 60 automatically. If the foot pedal is released at any time during the cutting cycle, both motors will be stopped and the procedure must begin again from the start, with the cutting assembly returning to the initial position before advancing once again.
To complete the operation, the surgeon depresses the foot pedal 32 to the reverse position returning switch 212 to its original state and closing switch 218. The second relay 214 is de-energized and direction switches 216 and 220 move to reverse positions. The cutting assembly 74 moves in a reverse axial direction opposite the forward axial direction until the slide member 52 trips the initial position microswitch 68 and switch 222 opens and stops the motor 50. As a result of the combination of switches tripped in sequence, this does not lead to the automatic forward axial cutting motion that started the operation.
In order to secure an accurate operation and to avoid injury to the eye, the suction pump 26 should operate at all times to hold the microkeratome 12 on the eye while the flap is being cut. Accordingly, it is desirable for the controller 28 automatically to shut off the rotary and axial motors 60 and 50, respectively, whenever suction is lost or falls below a predetermined value, as determined for example by a pressure sensor switch 212. When the pressure sensor switch 224 opens due to loss of suction the axial and rotary drive motors 50 and 60 are shut off. The only available operation is to depress the foot pedal 32 to the reverse position. The axial motor 50 then runs in reverse to return the slide member 52 and the cutting head 94 to the initial position. As mentioned above, the rotary motor 60 does not operate when the axial motor 52 is running in reverse.
Accordingly, unlike prior art LASIK systems, the present invention provides a system which includes a control assembly which is remote from the microkeratome and which permits independent operation of the transverse and axial motions of the cutting blade. Furthermore, the microkeratome according to the present invention is advantageously substantially transparent, lightweight and disposable.
Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described integers (components, assemblies, devices, compositions, etc.), the terms (including a reference to a "means" ) used to describe such integers are intended to correspond, unless otherwise indicated, to any integer which performs the specified function of the described integer (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
Patent | Priority | Assignee | Title |
7338508, | Sep 01 2000 | AZD HOLDING, LLC | Ophthalmic surgical system and method |
7802883, | Dec 20 2007 | Johnson & Johnson Vision Care, Inc | Cosmetic contact lenses having a sparkle effect |
Patent | Priority | Assignee | Title |
4173980, | Feb 25 1977 | Corneal resurfacing apparatus and method | |
4660556, | Feb 14 1985 | TECHNO OPHTHALMICS INTERNATIONAL, INC | Method and apparatus for modifying corneal buttons |
4662370, | Sep 13 1984 | HOFFMANN, FRIEDRICH | Apparatus for performing lamellar refractive corneal surgery |
4665914, | Dec 27 1985 | Automatic corneal surgery system | |
4674503, | Mar 05 1981 | Controlled depth penetrant apparatus and method | |
4688570, | Mar 09 1981 | The Regents of the University of California | Ophthalmologic surgical instrument |
4840175, | Jul 29 1985 | Chiron Vision Corporation | Method for modifying corneal curvature |
5108412, | May 14 1990 | Jorg H., Krumeich | Suction ring for surgical operations on the human eye |
5133726, | Feb 14 1990 | Automatic corneal shaper | |
5215104, | Aug 16 1988 | Method for corneal modification | |
5342378, | Oct 11 1991 | Micro Precision Instrument Company | Sectioning device for lamellar surgery |
5496339, | May 17 1994 | Universal automated keratectomy apparatus and method | |
5586980, | Oct 14 1994 | General Electric Capital Corporation | Microkeratome |
5591174, | Feb 02 1994 | Chiron Vision Corporation | Microkeratome and method and apparatus for calibrating a microkeratome |
5595570, | Dec 06 1994 | NEW UNITED DEVELOPMENT CORPORATION | Keratome with spring loaded adjustable plate, cutting length adjustment plate, method of cutting a corneal flap, and gauge-mounted bracket for adjusting plate on keratome head |
5624456, | Feb 07 1996 | Automatic surgical device for cutting a cornea | |
5658303, | May 16 1995 | Universal automated keratectomy apparatus and method | |
5690657, | May 17 1994 | Universal automated keratectomy apparatus and method | |
5779723, | Oct 30 1995 | SCHWIND EYE-TECH-SOLUTIONS GMBH & CO KG | Device for corneal surgery |
5817115, | Dec 04 1995 | BAUSCH & LOMB SURGICAL, INC | Apparatus for resecting corneal tissue |
5980543, | Dec 23 1996 | Instituto Barraquer de America | Microkeratome and method of performing corneal resections |
5989272, | Oct 05 1998 | Barron Precision Instruments L.L.C. | Keratome for performing eye surgery and method for using same |
5997559, | Aug 06 1997 | SIS LTD SURGICAL INSTRUMENT SYSTEMS | Microkeratome for performing lasik surgery |
6007553, | Apr 25 1997 | HELLENKAMP, JOHANN F | Automatic surgical device control assembly for cutting a cornea |
6022365, | Sep 04 1997 | Moria SA | Microkeratome for ophthalmological surgery |
6042594, | Oct 31 1996 | Positioning assembly for retaining and positioning a cornea | |
6126668, | Apr 25 1997 | INNOVATIVE OPTICS, INC | Microkeratome |
6228099, | Nov 21 1997 | AZD HOLDING, LLC | Ophthalmic surgical system and method |
DE19540439, | |||
EP873735, | |||
EP895764, | |||
RE35421, | Jul 27 1994 | General Electric Capital Corporation | Automatic corneal shaper |
WO9520920, | |||
WO9528871, | |||
WO9621406, | |||
WO9720529, | |||
WO9827901, | |||
WO9926568, |
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